Improvement in converting cast-iron into wrought-iron and steel



PATENT ()FFICEQ JAMES R. BI I'ADLEY, OF IRONTON, OHIO.

IMPROVEMENT IN CONVERTING CAST-IRON INTO WROUGHT-IRON AND STEEL.

Specification forming part of Letters Patent No. 34,937, dated April 15, 1862.

To all whom it may concern:

Be it known that I, JAMES R. BRADLEY, of Ironton, in the county of Lawrence and State of Ohio, have invented a new and Improved Method of Manufacturing Malleable Iron and Steel; and I hereby declare thatthe following is a full, clear, and exact description thereof, the ordinary and well-kuownmcthods of smelting the ores in hot or cold blast furnaces for the production of pig-iron being assumed as data.

My invention relates to the method of treating the cast-iron in the boiling furnace or in the puddling furnace, as the case may be; and it consists in the addition of certain reagents, which, by aidingin the decarbonization and purification of the metal, or by combining and forming therewith an alloy, or in both these ways, improve the quality of the resulting malleable iron or steel.

In order that others properly skilled in the manufacture of iron may be enabled to understand and use myinvention, I shall proceed to describe it in detail.

First, in relation to the manufacture of mal leable iron. It is well known that there are many different processes whereby the pig-iron of the blast-furnace is converted into malleable iron. Only two of these processes, however, need be particnlarized in order to the explanation of my invention. In the first process, which I shall distinguish by the letter A, the pig-iron from the blast-furnace is remelted in a boiling-furnace, where it is decarbonized and ultimately brought into a malleable condition, when it is removed in lumps to the squeezers, forges, or rolling-cylinders. In the second process, which I shall distinguish by the letter B, the cast-iron from the blastfurnace is remelted and partially decarbonizcd in the finery furnace or running-out fires, and afterward the fine metal is reheated aud puddledin a reverberatory furnace, and ultimately brought into lumps or balls in a malleable condition, ready for the action of squeezers, forges, cylinders, 800.

My invention is applicable to either or both of the above methods. I shall first describe it in connection with process A.

To a charge of four hundred or four hundred and fifty pounds of pig-iron in the boiling-furnace I add, in the order hereinafter indicated, the following reagents, viz: sulphate of the protoxide of iron,(green copperas,) four and one-half ounces, or thereabout; chloride of sodium, (common salt,) three pounds, or thereabout; binoxide of manganese, (black oxide manganese,) six ounces, or thereabout; protoxide of lead, (litharge,) three and onehalf ounces, or thereabout; ferrocyanide of potassium, (yellow prussiate of potash,) two and one-half ounces, or thereabout. The various quantities stated are about the average required; but as much depends on the quality of the iron, and also upon the appearance and behavior of the metal in the furnace, I do not propose to confine myself to the exact quantities herein named, but shall use more or less of each, as may under the circumstances be required.

The manner in which the process is conducted is as follows: After the iron and fuel are introduced, ignited, the damper raised, and the whole mass thoroughly melted,I introduce into the melted mass the sulphate of iron, and, placing the damper down,agitate with the paddles until the metal begins to swell and blubher from the escape of oxide of carbon or other gases. Next I introduce the common salt and agitate. Shortly afterward I introduce the oxide of manganese, afterward the litharge, and lastly the prussiate of potash. The iron must now be agitated and wrought with the paddles, rakes, &c., until it comes to nature, or is fit for transference to the squeezers, forges, or other working and compacting machines. In process 13 the ingredien ts are added in the same order as hereinbefore indicated, being thrown into the furnace when the metal has become pulvernlent and works dry. They are to be thoroughly mixed with the metal by paddling, and the process in other respects may be conducted after the ordinary manner. The damper may either be up or down; but by preference I work with it down after the reagents are added.

For the manufacture of steel direct from the cast-iron, I propose to add to about four hundred and eighty pounds of the melted metal in the boiling-furnace, or to an equal weight of the dry and pulverulent metal in the reverberatory furnace, chloride of sodium,four pounds, or thereabout; binoxide of manganese, two 0unces,or thereabout, and,when the gray iron is used, ferrocyanide of potassium, two and onehalf ounces, or thereabout, thoroughly incor= porating the various reagents in the order'in which I have named them, and with the same reservations relative to quantity which I have expressed in reference to the manufacture of 1ron.

Now, I aware that a triple compound ofor containing iron, carbon, and manganese has already been used and patented for a similar purpose to that set forth in my specification.

I am aware, also, that chloride of sodium and the binoxide of manganese have been usedin connection with potters clay for the same purpose. I do not therefore claim the use of any of these substances singly or in the combinations as set forth in the above disclaimer; but

What I claim, and what I desire to secure by Letters Patent, is this:

The use of the several substances set forth in the foregoing specification, substantially in the order, manner, and relative quantities set forth, for the purpose of more effectually and thoroughly converting'cast-iron into malleable iron or steel, as stated, respectively.

. JAMES It. BRADLEY.

Witnesses:

WM. OLOUGH, GEO. PYBURN. 

